I need to free up 4T on my LVM which is mainly taken by a Btrfs filesystem
mounted on /data
.
I did:
# btrfs fi resize -h
btrfs filesystem resize: too few arguments
usage: btrfs filesystem resize [devid:][+/-]<newsize>[kKmMgGtTpPeE]|[devid:]max <path>
Resize a filesystem
If 'max' is passed, the filesystem will occupy all available space
on the device 'devid'.
[kK] means KiB, which denotes 1KiB = 1024B, 1MiB = 1024KiB, etc.
so it looks I should do:
btrfs filesystem resize -4T /data
which gives an error:
Resize '/data' of '-4T'
ERROR: unable to resize '/data': Invalid argument
what am I doing wrong?
Best Answer
You seem to be running a newer version of the Btrfs tools
although the help has been updated (I get the same "help" message as you do in Btrfs tools v4.4), the command still only accepts
kKmMgG
.You should use:
to reduce the size by 4 terabytes.
Please note that contrary to some other tools that make a distinction between k=1000 and K=1024, for
btrfs filesystem resize
both lower and upper case this means multiples of 1024.